How do the American Express Velocity Platinum Lounge Passes work?

Has anyone used their Velocity Platinum Domestic Lounge passes?  Do you just show up to the counter and give them your card, or do you need to book your lounge pass before arriving at the airport?

The passes are loaded onto your VFF card so just show them your card when you arrive. You can login to the website first to check that they are loaded first.

When should we expect a VFF card? I signed up 3 weeks ago for the Amex card (which automatically created a VFF account), and while I got that the next week, still nothing on a VFF card. Do I need to request one specifically?